Arrangement for transforming mechanical energy into mechanical energy with intermediate transformation into electrical energy



April 1940. E. c. COURCOULAS 2,195,766

ARRANGEMENT FOR THANSFORMING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed March 12,1938 16 SheetsSheet 1 April 1940. E. c. COURCOULAS 2,195,766

ARRANGEMENT FOR TRANSFORMING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed March 12,1938 16 Sheets-Sheet 2 Fig. 2a.

5 age I a e EE/(E April 2, 1940- E. c. COURCOULAS 2.195.766

ARRANGEMENT FOR TRANSFORHING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed March 12,1938 16 Sheets-Sheet 3 Fig. 2 Z. 77/

29 .30 4L2 WWW I I I I L L5 MZZMM/w P" 2, 1940- E. c:v COURCOULAS2.195.766

ARRANGEMENT FOR TRANSFORMING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed March 12,1938 16 Sheets-Sheet 4 l i 25 J2 J l/l [Mum/EV l6 Sheets-Sheet 5COURCOULAS Filed March 12, 1938 ARRANGEMENT FOR TRANSFORIING MECHANICALENERGY INTO MECHANICAL ENERGY WITH INTERMEDIATE TRANSFORMATION INTOELECTRICAL ENERGY April 2, 1940- E c. COURCOULAS 2,195,766

ARRANGEMENT FOR TRANSFORMINC MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed March 12,1938 16 Sheets-Sheet 6 lllllil lfiilm 4 A %m r p i 1940- E. c COURCOULAS2,195,766

ARRANGEMENT FOR TRANSFORMING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed March 12,1958 16 Sheets-Sheet 7 Ap 1940- E. c COURCOULAS 2,195,766

ARRANGEMENT FOR TRANSFORMING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed March 12,1938 16 Sheets-Sheet 8 p 1940. E. c. COURCOULAS 2,l95.766

ARRANGEMENT FOR TRANSFORHING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed larch 12,1958 16 Sheets-Sheet 9 April 2, 1940.

E. C. COURCOULAS ARRANGEMENT FOR TRANSFORIIING MECHANICAL ENERGY INTOMECHANICAL ENERGY' WITH INTERMEDIATE TRANSFORMATION INTO ELECTRICALENERGY Filed March 12, 1938 16 Sheets-Sheet 1O p i 1940. E. c.COURCOULAS 2,195,766

ARRANGEMENT FOR TRANSFQRIING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed llarch 12,1938 I I I I I I I I II v.32 F

I /I-\38 49/ (17L fi 62 f 768 @Im om J2 I I l-l/lfi'u' I /3 {zMm/W 16Sheets-Sheet l1 April 2, 1940.

E. c. COURCOULAS 95,766

ARRANGEMENT FOR TRANSFORIING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed March 12,1938 16 Sheets-Sheet 12 Apnl 1940- E. c. COURCOULAS 2,195.766

ARRANGEMENT FOR TRANSFORIING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORIATION INTO ELECTRICAL ENERGY 7 Filed larch12. 1938 16 Sheets-Sheet 1s Fig. 7c.

O/WWL [and ni W 4} [Ki/M10 A ril 2, 1940.

E. C. COURCOULAS ARRANGEMENT FOR TRANSFORIING MECHANICAL ENERGY INTOMECHANICAL ENE WITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGYFiled March 12, 1938 M 7% a w w m w m Z .P, -.%L i k fl. mm N w r 0 6 W9 w m in w mm V mm & W 1* 1 m P 1940. E. c. COURCOULAS 2,195,766

ARRANGEMENT FOR TRANSFORIING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed larch 12,1938 16 Shee ts-Sheet 15 p 1940. E. c. couhcouLAs 2,195,766

ARRANGEMENT FOR TRANSFORIING MECHANICAL ENERGY INTO MECHANICAL ENERGYWITH INTERMEDIATE TRANSFORMATION INTO ELECTRICAL ENERGY Filed larch 12,1938 16 Sheets-Sheet 16 Jig. c5 c.

Patented Apr. 2, 1940 UNITED STATES PATENT OFFICE Emmanuel Courcoulas,Asnieres. France, assignor to the firm "Sebrev" Socit dEtudes et deBrevets, Geneva, Switaerland Application March 12,

1938, Serial No. 195,820

In Swltleilaml. May 28, 1987 30 Claims.

The invention relates to systems intended for the transfer of mechanicalenergy into energy of the same kind by intermediate conversion intoelectrical energy.

I The system comprises for this purpose at least one primary source 01'mechanical energy such as an electric motor producing a driving torquedependent on the energy input applied to a prime mover driving it, and acontrol member making it possible to vary as desired the energy input tothe prime mover in question. This prime mover may be a water turbine ora steam engine with its sluice or throttle valve, an internal combustionengine with an accelerator by which the injection or the energy input offuel or of an explosive mixture can be varied, an electric motor withits regulating rheostat, or the like.

The system additionally comprises a generator group of at least one unitgenerating electrical energy, which is coupled to the primary source ofmechanical energy and imposes on it a resisting torque dependent on theload demand of a motor group 01' at least one unit. This motor groupabsorbs practically all the electrical energy produced by the generatorgroup and delivers it in the form of secondary mechanical energy,constituting the energy which it is desired to obtain after electricaltransformation.

' vided by which the magnetic fluxes oi the units in the generator andmotor groups are subjected I to change each time the feed supply to theprime mover varies; in consequence oi which a 35. variation is also madein the strength of current supplied by the generator group to the motorgroup. At the same time a change is made in the value of the resistingtorque exerted on the moving part of a regulating device. This movingpart additionally is subjected to an electromagnetic iorce proportionalto the resisting torque of the generator group which resisting torqueproduces a reduct on of flux in the units of this group and an increaseof flux in the units of the motor group at such times as theelectromagnetic force exceeds the opposing or resisting force, producinga momentary unbalance in the regulating device.

It is possible for example to provide either for direct action of themember controlling the input of the fluid or the like on the flux valuesto be changed, or to derive this action from the primary source ofmechanical energy by utilising fill for this purpose for instance themean pressure According to my invention means are promaintaining in thecylinders in the case of a heat engine.

When the motor group comprises a single unit, the variation of itsmagnetic flux can be obtained for instance by providing for this unitindependent excitation capable of regulation. In the case of severalunits my invention can be extended to include the further feature oivarying the method oi connecting the units together, and similar changescan be provided in the case of the generator group.

According to another embodiment of this invention, the units of themotor grqup can be divided into at least two sub-groups, each subgrouphaving at least one separate exciter, these exciters however beingcompulsory connected together and to the primary source of mechanicalenergy, means being provided making it possible to vary independentlythe value and the direction of the excitation of the exciters in eachsub-group, said means making it possible to distribute all theelectrical energy absorbed by the motor group at will between thesub-groups of the latter.

This arrangement presents particular advantages when the units of themotor group are divided into two sub-groups and when the system isapplied to any vehicle, by making one of the sub-groups act on thedriving means on one side of the vehicle and the other sub-group on thedriving means on the other side of the vehicle. By actuating the meanswhereby all the electrical energy absorbed by the motor group can bedistributed at will between the subgroups of the latter, it is possibleto move and to direct the vehicle with facility in all directions and atall speeds.

The vehicle in question can for example take the form of a land vehiclehaving wheels or caterpillars, or it may be a boat actuated bypaddle-wheels, propellers, etc.

Finally, it is clear that the claimed system constitutes a reversibleassembly, since it absorbs and delivers energy in an identical iorm.Reverse operation may for example be utilised for regenerating brakingwhen the system is fed by an original source of electrical energy.

The accompanying drawing shows diagrammatically several constructionalforms of the subject-matter of my invention, given solely asillustrative and by way of example, and therein Figure l is a greatlysimplified typical diagram intended to illustrate the principleconstituting the basis of the invention,

Figure 2a, 2b and 2c combine together to form a complete diagram oi oneform of construction, in which a single electric generator driven by aninternal combustion engine ieeds a reversible electric motor which canalso act as a brake, the complete assembly may be depicted by arrangingthese three views side by side.

Figure 3 is a diagram showing the manner in which four motor units canbe coupled together by means 0! two multipole change-over switches,

Figures 4a, 4b, 40, when joined together side by side, constitute acomplete diagram of a second form of construction in which a singleelectric generator driven by an internal combustion engine reeds fourelectric motors all driving a mechanical member at the same speed, themotors being connected together electrically according to the diagram oiFigure 3.

Figure 5 is a partial diagram showing the manner in which entirelyautomatic operation oi the connections provided in the diagram 0! Figure4 can be obtained, and

Figure 6a, 6b, when joined together side by side, constitute a completediagram of automatic connections in the case of two generator units andtour motor units, with possible modification of the connections of thearmatures and fields for both generator and motor groups.

Figures Ia, 1b, 1c, when Joined together side by side, constitute thecomplete diagram of a system comprising two motor sub-groups andrelating to the case of driving a vehicle. This diagram shows saidsystem with the exception of the generator members, i. e. in the absenceof the internal combustion engine and the generator. The main circuit Io! the motors is therefore broken 01!.

Figures Ia, Ib, Ic, when joined together side by side, constitute acomplete diagram of a system of the same type as Figure '7, butcomprising two motors in each sub-group.

Gasman Dsscarmos Referring to the tic Figure 1, an electric generator Iis directly coupled to and driven by an internal combustion engine 2constituting the primary source or mechanical energy for the plant. Anelectric motor I driven by the electrical energy thus producedtransforms and delivers this latter in the form of secondary mechanicalenergy capable of driving any machine such as that diagrammaticallyrepresented by the rectangle I.

The motor I absorbs substantially all the energy produced by thegenerator I, as indicated by the heavy lines of the circuit Iinter-connecting the armatures of these two machines. The coil I o! aregulating device inserted in this circuit absorbs only a negligibleamount of energy.

Generator i and motor I are provided with separate excitation, derivedfor instance from a battery I for the generator and a battery I for themotor, the value of the corresponding excitation fluxes being capable ofvariation by rheostats or other suitable controls I and II respectively,having corresponding sliders Ii and i2 movable therealong. The iieldcurrent of the generator i also passes through a coil II of theregulating device.

A rotary member II, which can be displaced as desired by hand or foot,constitutes the accelerator member or pedal oi the internal combustionengine 2, as indicated diagrammatically by the dotted line ll betweensaid pedal or lever and the lever It or a butterfly valve, not shown.The movement of this valve increases the inputortheexplosivemixtureaocordingtoapredetermined law when the member II ismoved inthedirectionoithearrowl'i.

Accelerator member II is mechanically connected to the resistance of therheostats I and I II as indicated by the dotted line II and is alsoconnected as by elastic means indicated diagrammatically as a spring II,to the moving part II of the regulating device.

Thus by actuating the member II in the direction of the arrow iladmission or energy input is increased, thereby increasing the torque ofthe internal combustion engine I. Simultaneously therewith theexcitation of the generator i and that of the motor I are caused to varybecause 16 o! the bodily movement of the resistances themselves therheostats I and II relative to their sliders ii and it. When. theaccelerator is opened. the excitation of both the generator and themotor is increased, which causes the iiux in both machines to rise. Thespring II is tensioned by movement of the member it, so that its biasingaction on the moving part II of the regulating device is increased. Thisopposing force or biasingaction,whichinpracticewillbecausedto varyproportionately to the torque developed by the internal combustionengine, opposes the combined electro-magnetic action of the coils I andII, the action'oi which latter is proportional to the resisting torqueof the generator I, since it combines a factor proportional to thecurrent supplied to the line I, with a factor which is dependent on theneld current of the generator, and consequently is proportional to itsiield flux, care being taken to ensure proper generator core design.

Depending upon whether or not the electromagnetic action or resistingtorque overcomes the purely mechanical biasing action 01' the spring II,the moving part II 0! the regulating device will turn to one side or theother in Figure 1, thus moving the sliders Ii and I! of the iieldrheostats I and II by means of mechanical connections indicateddiagrammatically by dotted linu Ii, 22, reversing means comprising atransmimion lever such as the rocker II ensuring that the sliders aremoved in opposite directions upon movement of part or arm II.

when the combined electro-magnetic action oi-thecoilsIandiIovercomesthatoithespringulIsndbyconsequencethemovingpartIIoithe regulating device rotates in thedirection of the arrow 24, the excitation of the generator diminishes,while that of the motor increases. In short the action 0! the movingpart of the regulator tends to diminish the flux of the generator I andto increase that oi the motor I.

The described system could be applied for example to the drive of amotor rail vehicle, the vehicle being controlled by the manipulation ofthe accelerator lever II; and, when it is desired to stop the motor Icompletely or to test the systemonopencircuitbyaswitchflinthecln cuit I.The driven member I would then be constituted by at least one motor axleof the vehicle.

'Iheenginelbeinginactiomallthatisneceasarytoensurestartingandaccelerationoithevehicleistoclosetheawitch Ilandthentoaccelerate the engine. Theacceleration of the engine I, caused by increasing the fuel supply,increases the developed driving torque and to the extent that thistorque exceeds the resisting torque, back E. M. F. o! the generator I,the generator speed being accelerated and the powerwhichitsuppliestoitsterminalsiincreasing. u

The developed voltage likewise rises because of the reduction of theresistance in the field rheostat 9, due to the movement of the lever llgiving rise to a corresponding increase of flux produced. A simultaneousincrease of the field flux of the motor which momentarily exceeds thedemagnetizing action brought about by operation of the regulator 20,builds up therein the torque and energy necessary for the correspondingacceleration of the vehicle, increased energy being available from thecircuit 5.

Upon rise in output-current flow in circuit 3 the excitation of the coil3 increases, while upon decrease of value of resistance 9, theexcitation of coil I3 likewise increases, the combined action tending tocause the moving part 20 of the regulating device to turn in thedirection of a reduction of fiux in the generator I and an increase offlux in the motor 3, i. e. in the direction of arrow 24, in order toregulate the resisting torque of the generator and thus to tend toprevent any reduction of its speed, while maintaining constant thequantum of energy transmitted from the generator to the motor. I

' For satisfactory operation this regulating action should in no casecome into operation except when the load demand tends to exceed theinstantaneously developed torque of the internal combustion engine 3operating at its maximum efficiency. This is precisely what happens inthe system disclosed, since the moving part 20 of the regulating deviceis subjected to increased pull by the spring I9 upon increase in thedrivin torque caused by movement of member ll in the direction of thearrow I1, and does not start its regulatory action until the attractionof coils 6 and I 3 exceeds the biasing action of the spring I9.

In practice. the regulating device will be adjusted in combination withthe spring I! for control by the accelerator member I4, which adjustmentwill fix the force exerted by the spring either at a constant valueproportional to the maximum torque of which the internal combustionengine is capable of developing in the case of constant opening of thethrottle valve; or at values variable in dependence upon the position ofthe member I in accordance with an arbitrarily chosen law, In the firstcase, with constant throttle opening, the variation of speed of thegroup is obtained by the variation of the electric resisting torque orback E. M. F. of the generator consequent upon the displacement of theresistances 9 and I0; and in the latter case the variation is obtainedby supplementing this action by the variation of developed torque of theinternal combustion engine upon variation in throttle opening.

Moreover it is evident that the movement of the regulating member couldbe effected by any means other than a spring so long as it actsproportionally to the torque developed by the internal combustionengine, for instance by the displacement of a piston under the action ofa pressure proportional to the mean pressure maintaining in thecylinders of the engine.

The driver could thus adjust at will the power output of the internalcombustion engine 2 to the speed desired for the vehicle. The regulatingdevice for its part would automatically adapt to this power output aminimum fuel supply of the engine so as to utilise completely the powercapable of being developed in this condition of the engine. If too muchfuel were supplied, speed would tend to increase, so that properthrottle setting could be quickly ascertained. Finally the systemdescribed will automatically transform the power supplied from a fixedthrottle setting into either a small torque and high speed, or a hightorque and low speed, according to the gradient of the track, byvariation of current flowing in coil 0.

Similarly, whatever may be the characteristic of the driving torque ofthe internal combustion engine 2, the system described willautomatically adapt the characteristic of the resisting torque of thegenerator, to that of the engine, from which results an operation of theengine 2 which involves a minimum of wear and of consumption of fuel,since the engine constantly operates in the neighbourhood of its maximumtorque and efilciency.

Susana Gnrzm'roa Surname Rs'vnasrau: Moron (Figs. 2a, 2b, 2c)

The first form of construction according to Figure 2 which employs thebasic system of Figure 1, can be applied equally as well to the drive ofa rail vehicle or a road vehicle; but the latter, however, requires theusual steering mechanism in addition to the mechanism about to bedescribed.

The following parts comprised in the diagram of Figure l are designatedin Figure 2 by the same references: the electric generator I; theinternal combustion engine 2; the electric motor 3; the members 4 drivenby this motor; the circuit 5 connecting together the armatures of thegenerator and motor and passing through the coil 6 of the regulatingdevice; the resistances 8 of the generator field rheostat and iii of themotor field rheostat and the corresponding sliders II and I2; thearmature winding I3 of the regulating device constructed as the armatureof an electric motor, this winding likewise being connected to the fieldof the generator I; the accelerator pedal I4 acting, as will be seen, onthe throttle I8 regulating the fuel intake to the internal combustionengine 2, the arrow I'I showing the direction of movement of the pedalfor acceleration; the spring l9 which is constructed to exert a torqueon the moving part 20 constituting the armature of the regulatingdevice; the rocker 23 intended to reverse the regulating action appliedto slider I2 relative to that applied to the slider II; and finally theswitch 25, shown here as replaced by a single-pole double-throw switch,by means of which the armature of the motor 3 can be shortcircuitedthrough a braking resistance denoted by 26.

The generator I is provided with a separate exciter 21 and the motor 3with a separate exciter 23, both mounted on an extension of the shaft ofthe engine 2, along with the generator I. The excitation of thesegenerators is derived in turn from batteries 29, 30, corresponding ingeneral to batteries 1 and 8 of Figure 1, and having for example aterminal voltage of 12 volts each.

The generator I and the motor 3 are both in direct connection with theirexciters, one by the circuit 3| passing through the winding I3 and theother by the circuit 32 to the armatures of exciters. Variations ofgenerator and motor fiux are obtained by varying the exciterfieids, forwhich purpose these field circuits pass through the correspondingresistances 9'and III by means of the following circuits; for theexciter, 21, positive pole of the battery reversing switch 33, switch34, leads 35 and 36 with the field of exciter 21 interposed, resistance9 and lead 31 passing to the negative pole of the reversing switch.

33 for the generator; and for the exciter 23, positive pole of thechange-over switch 33, lead 33,

' contact 33, segment 43, contact 4|, leads 42 and 31, resistance I3,leads 43 and 44, field of exciter 23, lead 45, contact 43, segment 41,contact 43, lead 43 and return to the negative pole by 31 as before.

The tracing of the two foregoing circuits is on the basis that thechange-over switch 33 is connected to one of the batteries 23 and 33;that the switch 34 is closed and that the lever 53 of thedirection-determining apparatus is displaced in the direction of thearrow 5I. Should the lever 53 be displaced in a counter-clockwisedirection, the field circuit of the exciter 21 for the generator willremain unchanged, while the field circuit of the exciter 23 for themotorwill pass through the following circuit: positive pole of thechange-over switch 33, lead 33, contact 52, segment 41, contact 53, lead43, field of exciter 23, leads 44 and 43, resistance I3, lead 51 and 42,contact 4I, segment 43, contact 54 and return to the negative pole bythe leads 43 and 31.

As will be seen, the current does not pass through the exciter 23 in thesame direction in both cases, it passing from the lead 44 to the lead 45in the first case and from the lead 45 to the lead 44 in the latter. Thereversal of the direction of the fiux thus produced in the motor 3 makesit possible to reverse the direction of ro tation of the motor simply bymanipulating the lever 53. Moreover, in the rest position of lever 53 asshown the motor 3 is not excited, since the field circuit of its exciter23 is open, not only because of the segment 43 of lever 53 is out ofcontact with the contacts 33, 4| and 34, but also because the segment 41of the said lever is out of contact with the contacts 43, 43, 52 and 53.

It should be mentioned that the field circuit of the exciter 23 for themotor 3 is influenced not only by the resistance I3 but also by a secondvariable resistance 55 in parallel with the latter by means of the leads53 and 51 connected to the leads 43 and 44. This second resistance actsduring braking, being normally fully connected in circuit as shown bythe rest position illustrated in Figure 2, so that current flowtherethrough is effectively blocked during normal operation of thesystem. The braking action will be described later.

The system thus described operates in the following manner: The internalcombustion engine 2 is started by operation of the generator i after theswitch 33 has been closed on to one of the batteries 23 and 33 (to bedescribed in the next paragraph) followed by the closing of the switch34. This latter not only closes the field circuit of the exciter 21 forthe generator but also feeds the ignition coil 53 for the internalcombustion engine, without which the latter could not operate. Finally,the switch 34 has the third function of permanently opening the mainsupply circuit 5 to the motor 3 so long as the lever 53 of thedirection-determining device is in its illustrated rest position, thisbeing brought about by its closure of the following circuit: positivepole of the switch 33, switch 34, lead 35, electromagnet 53 for thedouble throw switch 25, lead 33, contact 3I, segment 32, brush 33 andreturn to the negative pole of switch 33 by leads 43 and 31. Theelectromagnet 53 being thus energized, the armature of the double throwswitch 25 is lifted to the braking position, and the circuit 5 ismaintained open.

To start up the system, switches 33 and 34 are closed, following whichthe switch 34 is closed. the latter completing a starting circuitconstituted by the positive pole of the two batteries 23 and 33 inseries, the above-mentioned switch 34, the lead 35, a separate startingfield winding on the generator, the lead 33, a shunt branch of thecircuit 5 comprising the generator armature, and the lead 31, returningto the negative pole of the two batteries. The generator I then startsthe internal combustion engine 2.

At the same time a circuit is set up, as a shunt on the startingcircuit, starting from the lead 33, acting as positive pole, through thelead 33, the fan motor 33, the lead 13 and the winding H of thecontactor 12, and back to the main starting circuit at 31, this shuntcircuit closing said contactor 12.

With contactor 12 thus being closed, then when the switch 34 is opened,the following charging circuit for the batteries is set up: positivepole of the generator I, leads 33 and 33, fan motor 33, lead 13,contactor 12, positive pole of the battery 23 in series with the battery33, negative pole of the latter and return to the negative pole of thegenerator by the lead 31 and a shunt on the circuit 5. Thus the chargingof the battery is eifected from the generator through the fan motor ofthe internal combustion engine, which latter is thus cooled morestrongly, upon increase of the output of the generator I.

It nevertheless is apparent that the quantity of current diverted inthis way is small in comparison with the load current to motor 3supplied by the generator I, rendering valid the statement that themotor absorbs practically all the current output of the generator.

Once the internal combustion engine is started, it can be accelerated bymeans of the pedal I4. Moreover, it will be seen that the field of theexciter 21 for the generator has been preliminarily energized as soon asthe switch 34 is closed, which makes it possible for it to functionimmediately supplying field current for generator I.

The energization of the motor 3 in a selected direction is then broughtabout by operating the lever 53 of the direction-determining device inthe desired direction. When that is done, the segment 32 is firstremoved from the contacts 3| and 33 and thus the excitation current ofthe electromagnet 33 is cut causing the double pole switch 25 to fallinto the position shown in the drawing, in which it closes the feedcircult 5 to the motor 3. Further movement of lever 33 results in theexcitation of the exciter 23 for motor 3 in the direction chosen, themotor 3 in its turn being excited over circuit 32 and starting up in thedirection determined by the above operation.

It now, the internal combustion engine 2 is accelerated by pedal I4, thefollowing occurs: The movement of the accelerator pedal I4 in thedirection of the arrow I1 causes an upward pull on the rod 13 and apivoting of the bell crank lever 14, moving the rod 13 in the directionof the arrow 13. The resistance elements of the rheostats 3 and I3, anda cam 11, all mounted on rod 15, are bodily carried along with the rod15. There results a simultaneous decrease in the values of theresistances inserted in the field circuits of the generator and motorexciters,-and a raising of the rod 13, controlled by 15

